As a quick follow up to Luis's post, once you can see / view the file extension type (i.e.: after selecting the view extensions check box), you will likely find that you're 'php.ini' file actually has the file name... 'php.ini.ini'.
Consequently, you just need to delete the .ini suffix from the end of this file - i.e.: so the file is now named... 'php.ini' and hey presto, you should find that this fixes the problem
Best of luck